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package Q6;
import java.util.*;
public class WeekDay {
public static final int JANUARY = 0;
public static final int FEBRUARY = 0;
public static final int MARCH = 0;
public static final int APRIL = 0;
public static final int MAY = 0;
public static final int JUNE = 0;
public static final int JULY = 0;
public static final int AUGUST = 0;
public static final int SEPTEMBER = 0;
public static final int OCTOBER = 0;
public static final int NOVEMBER = 0;
public static final int DECEMBER = 0;
public static final int SUNDAY = 0;
public static final int MONDAY = 1;
public static final int TUESDAY = 2;
public static final int WEDNESDAY = 3;
public static final int THURSDAY = 4;
public static final int FRIDAY = 5;
public static final int SATURDAY = 6;
private static final String[] DAYS =
new String[] {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"};
private static final int[] MONTHS = new int[] {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
public String getWeekDay(int day, int month, int year) {
return DAYS[daysSinceEpoch(day, month, year) % 7];
}
private int daysSinceEpoch(int day, int month, int year) {
int days = (year - 1900) * 365;
days += (year - 1900) / 4;
if (isLeapYear(year) && (month == 1 || month == 2)) days -= 1;
days += daysThisYearUpTo(day, month);
return days;
}
private boolean isLeapYear(int year) {
return year % 4 == 0;
}
private int daysThisYearUpTo(int day, int month) {
int days = 0;
for (int i = 1; i < month; i++) days += daysInMonth(i);
return days + day;
}
private int daysInMonth(int month) {
return MONTHS[month - 1];
}
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
System.out.println("Enter year:");
int year = in.nextInt();
System.out.println("Enter month:");
int month = in.nextInt();
System.out.println("Enter day:");
int day = in.nextInt();
System.out.println(new WeekDay().getWeekDay(day, month, year));
}
}
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